The patch titled
acpi_evaluate_integer: avoid using kmalloc()
has been added to the -mm tree. Its filename is
acpi_evaluate_integer-avoid-using-kmalloc.patch
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------------------------------------------------------
Subject: acpi_evaluate_integer: avoid using kmalloc()
From: Pavel Machek <pavel@xxxxxxx>
Now I know why I had strange "scheduling in atomic" problems:
acpi_evaluate_integer() does malloc(..., irqs_disabled() ? GFP_ATOMIC
: GFP_KERNEL)... which is (of course) broken.
There's no way to reliably tell if we need GFP_ATOMIC or not from code,
this one for example fails to detect spinlocks held.
Fortunately, allocation seems small enough to be done on stack.
Signed-off-by: Pavel Machek <pavel@xxxxxxx>
Cc: "Moore, Robert" <robert.moore@xxxxxxxxx>
Cc: "Brown, Len" <len.brown@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/acpi/utils.c | 16 ++++------------
1 file changed, 4 insertions(+), 12 deletions(-)
diff -puN drivers/acpi/utils.c~acpi_evaluate_integer-avoid-using-kmalloc drivers/acpi/utils.c
--- a/drivers/acpi/utils.c~acpi_evaluate_integer-avoid-using-kmalloc
+++ a/drivers/acpi/utils.c
@@ -259,34 +259,26 @@ acpi_evaluate_integer(acpi_handle handle
struct acpi_object_list *arguments, unsigned long long *data)
{
acpi_status status = AE_OK;
- union acpi_object *element;
+ union acpi_object element;
struct acpi_buffer buffer = { 0, NULL };
-
if (!data)
return AE_BAD_PARAMETER;
- element = kzalloc(sizeof(union acpi_object), irqs_disabled() ? GFP_ATOMIC: GFP_KERNEL);
- if (!element)
- return AE_NO_MEMORY;
-
buffer.length = sizeof(union acpi_object);
- buffer.pointer = element;
+ buffer.pointer = &element;
status = acpi_evaluate_object(handle, pathname, arguments, &buffer);
if (ACPI_FAILURE(status)) {
acpi_util_eval_error(handle, pathname, status);
- kfree(element);
return status;
}
- if (element->type != ACPI_TYPE_INTEGER) {
+ if (element.type != ACPI_TYPE_INTEGER) {
acpi_util_eval_error(handle, pathname, AE_BAD_DATA);
- kfree(element);
return AE_BAD_DATA;
}
- *data = element->integer.value;
- kfree(element);
+ *data = element.integer.value;
ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Return value [%llu]\n", *data));
_
Patches currently in -mm which might be from pavel@xxxxxxx are
linux-next.patch
backlight-catch-invalid-input.patch
backlight-catch-invalid-input-checkpatch-fixes.patch
acpi_evaluate_integer-avoid-using-kmalloc.patch
strict_strto-is-not-strict-enough.patch
lis3lv02d-separate-the-core-from-hp-acpi-api.patch
lis3lv02d-merge-with-leds-hp-disk.patch
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